Possible cause
Swim Bladder Disorder
Trouble staying balanced — floating, sinking, swimming sideways or upside down — usually points to swim bladder disorder. It's often caused by overfeeding or constipation and frequently resolves with a few days of fasting, though poor water quality can also be a contributing factor worth ruling out.
Why this happens
- Overfeeding or swallowing air while eating floating food is the most common cause, especially in goldfish and bettas.
- Constipation from a diet too high in dry pellets and too low in fiber can put pressure on the swim bladder.
- Less commonly, a bacterial or parasitic infection, or a physical injury, can affect the swim bladder directly.
What to do next
- Fast the fish for 24-48 hours to let its digestive system reset.
- Offer a skinned, cooked pea (or other fiber-rich food) after fasting to help relieve constipation.
- Soak dry pellets in water for a few minutes before feeding to reduce swallowed air.
- Test your water to rule out a quality issue if symptoms don't improve within a few days.
Frequently asked questions
Will swim bladder disorder go away on its own?
Often yes, within a few days of fasting and dietary changes, if the cause is overfeeding or constipation rather than infection.
Can fish recover from swim bladder disease?
Most cases caused by diet resolve fully with fasting and fiber; if it persists more than a week, water quality or a low-grade infection may be the actual cause.